基于汉字使用频率的文本零水印算法  

Text zero-watermark based on use frequency of Chinese characters

作　　者：王晓龙[1] 严承华[1] 

机构地区：[1]海军工程大学信息安全系,武汉430033

出　　处：《计算机应用》2009年第9期2366-2368,2382,共4页journal of Computer Applications

摘　　要：针对汉字文本数字水印嵌入复杂,水印透明性不佳,鲁棒性不高以及水印容量不足等现实问题,提出了一种基于汉字使用频率的文本零水印算法,通过统计文本中汉字使用频次,然后结合常用汉字使用频率表,提取文本特征来构造零水印,鉴于该水印算法的特点,定义了一种特殊相关函数,用于确定阈值以及检测水印。实验结果表明该方法构造的水印算法具有很好的透明性、鲁棒性和足够的水印容量,用该相关函数构造的检验算法误检率相当低。Aiming at the problems of difficult embedding of Chinese text digital watermark, poor imperceptibleness and robustness and lack of watermark capacity, a zero-watermark algorithm based on use frequency of Chinese characters was presented. In this algorithm, the use frequency of Chinese characters in the text was calculated, and then combining the frequency table of commonly used Chinese characters, the text characteristic was extracted to construct a zero-watermark. According to the trait of the watermark algorithm, a correlation function was defined to fix threshold value and examine the watermark. Experimental results indicate that the watermark algorithm constructed in this way has good imperceptibleness, robustness and sufficient watermark capacity, and the constructed watermark examining algorithm based on the correlation function exhibits comparatively lower misjudging rate.

关 键 词：文本零水印 特征提取 相关函数 鲁棒性 透明性 时间戳 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]